No evidence that styrene exposure causes cancer: study

There is “no credible evidence” that styrene exposure increases the risk of cancer in humans, according to a new study.

The study, “Cancer Mortality of Workers Exposed to Styrene in the US Reinforced Plastics and Composite Industry”, surveyed nearly 16,000 styrene-exposed workers and found no credible evidence that such exposure increases the risk from cancers of the lymphatic and hematopoietic tissue, pancreas or lungs.

“These findings, which are based on 60 years worth of epidemiology data on cancer risks associated with workers exposed to relatively high levels of styrene, completely undercut the US National Toxicology Program’s listing of styrene as ‘reasonably anticipated to be a human carcinogen’ in its 12^th Report on Carcinogens,” said Jack Snyder, executive director of the Styrene Information and Research Center (SIRC), which supported the study.

The study adds 19 years of follow-up mortality data to a study of workers in the reinforced plastics industry published originally in 1990 and updated in 1994.

“This updated analysis substantially adds to the evidence that indicates a lack of association between styrene exposure and cancer,” said Julie Goodman, a toxicologist with Gradient. Goodman co-authored a recent weight-of-evidence analysis of styrene research, concluding that studies in humans, and particularly workers with high styrene exposures, show no consistent increase in death from any type of cancer.

Since June 2011, SIRC and its members have been fighting the inclusion of styrene as an anticipated human carcinogen in the National Toxicology Program’s 12th Report on Carcinogens.

The new study has been published in the peer-reviewed journal Epidemiology’s March issue.